Government ministers are scrambling to put together a plan to control immigration because of fears Emmanuel Macron will crack down on UK border controls in Calais.
That's according to The Telegraph, which claimed ministers are worried that Macron, who has previously issued several tough statements on Brexit, will take a hardline against the UK.
When he was a candidate, the En Marche leader vowed to renegotiate and change the terms of the Le Touquet agreement, which grants UK border officials to power the conduct checks on French soil - and thus allows Britain to maintain a de facto border in Calais.
While he has softened his position slightly in recent months, the new president has made it clear he will still seek to renegotiate the agreement.
Now, in the wake of his victory on Monday, ministers are drawing up plans to stop illegal immigration into the UK.
The Telegraph claims to have been told that, if the Calais border is scrapped, the responsibility of stopping illegal immigrants will fall to the ferry companies, with a potential £2,000 fine per illegal immigrant discovered.
Theresa May has implied the arrangement will need to be examined again, though she has promised to defend it by claiming it benefits France just as much as the United Kingdom.